Rudolf Steiner School on toxic land

A Christchurch school has cordoned off toxic areas in its grounds ahead of an $84,000 clean-up.

Rudolf Steiner School in Opawa was built on a former landfill site and has been named one of New Zealand's top ten most toxic sites.

Environment Minister Amy Adams has announced an initiative, which identified and ranked sites for clean-up under the contaminated sites remediation programme.

Rudolf Steiner School, built on a former landfill, was tenth on the list.

It has been granted a $42,000 towards the cost of remediating the soil, which contained lead and arsenic.

Rudolf Steiner School principal Thomas Proctor said he was "surprised" the school had been prioritised, as the levels of lead and arsenic found in the soil were "just above" the new national environment standards introduced in 2012.

He said the proprietor had gone beyond best practice to make sure pupils were safe, cordoning off 200 square metres in the kindergarten and five square metres on the school grounds 18 months ago.

He said it was common knowledge the school had been built on a landfill, and parents were "very happy" the sites had been cordoned off. Professional consultants had ensured the area was safe.

The standards allowed for 20 mg of arsenic per kg of soil for a residential area, and 80 mg for a recreational area.

Proctor said levels of arsenic found on the school site were 25 mg per kg of soil, and levels of lead ranged between 270 and 580 mg per kg of soil.

Environment Minister Amy Adams said relative to the other sites on the priority list, the Steiner School had "significantly lower concentrations and mass of contaminants" so was the least toxic of the sites on the priority list.

"The school's presence on the priority list is primarily due to the potential for children to be exposed to these contaminants."

The total cost of the investigation and remediation processes would be $150,000, the second lowest cost for all 10 sites on the list.

Proctor said the $42,000 grant was "a fantastic win-win for us all". "The Ministry is clearly showing concern about contamination in public spaces."

The affected 300 cubic metres of soil would be put on a "less sensitive site" on a block of land recently purchased by the school, covered with 50cm of clean soil and turned into a playing field during the school holidays next month, Proctor said.

The site would also undergo an assessment of the landfill cap, and a long-term a site management plan would be developed.

Sites were identified using a environmental risk management tool to quantify the level of risk at each site.

The ten priority sites (remediation costs in brackets):

Prohibition Mine, Waiuta, West Coast (Still to be determined)

Alexander Mine, Grey Valley, West Coast (Still to be determined)

Kopeopeo Canal, Whakatane ($11,164,900)

Calwell Slipway, Port Nelson ($184,631)

Te Mome Stream, Seaview, Lower Hutt (No cost given)

Miramar Gasworks, Miramar, Wellington (No cost given)

Onehunga Aquifer, Onehunga, Auckland ($2.56m)

Rotowaro Carbonisation Plant, 8km north west of Huntly, Waikato ($270,996)